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  1. MariaDB Server
  2. MDEV-21029

Incorrect result for expression with the <=> operator and IS NULL

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Details

    • Bug
    • Status: Confirmed (View Workflow)
    • Major
    • Resolution: Unresolved
    • 5.5, 10.0, 10.1, 10.2, 10.3, 10.4, 10.5
    • 10.4, 10.5
    • None
    • None
    • Ubuntu 19.04

    Description

      Hi everyone,

      On the latest trunk version (0308de9), I could observe a bug, as demonstrated by the following test case:

      CREATE TABLE t0(c0 INT);
      		 
      INSERT INTO t0 VALUES (1);
      		 
      SELECT (c0 > (NULL <=> 0)) IS NULL FROM t0; -- expected: 0, actual: 1

      The expression seems to work correctly when it is used in a WHERE condition:

      SELECT * FROM t0 WHERE (c0 > (NULL <=> 0)) IS NULL; -- no row is fetched

      Attachments

        Issue Links

          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-21034 GREATEST() and LEAST() malfunction for NULL

          • Major - Major loss of function.
          • Confirmed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-21065 UNIQUE constraint causes a query with string comparison to omit a row in the result set

          • Major - Major loss of function.
          • Closed

          Activity

            People

              igor Igor Babaev
              mrigger Manuel Rigger
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              Dates

                Created:
                Updated:

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